(a) If in a territory added to a municipality a retailer erroneously collects an amount as a tax imposed under this chapter before the date the taxes imposed under this chapter by the municipality take effect in the added territory under Section 321.102, the amount collected is treated as if it were revenue from the taxes imposed by the municipality under this chapter, and the comptroller shall collect and administer the amount in the same manner as tax revenue.
(b) This section does not affect the right of a person who paid an amount erroneously collected by a retailer to claim a refund or the authority of the comptroller to make a refund of that amount.